Avanços na Pesquisa em Ciências Aplicadas Acesso livre

Abstrato

The effects of selection for multiple traits on diversity of advanced wheat lines revealed by molecular markers

Noori A, Ahmadikhah A, Soughi H, and Dehghan M

It was suggested that selection for multiple desirable traits during generations has meaningful effects on diversity of resultant lines to be released to farmers. However, this idea less was studied at molecular level. We have started investigating effects of selection on diversity of wheat advanced F5 and F6 lines derived from Falat//ATTILA/BCN13/MILLAN/SHA7 cross, which passed 5 and 6 generations of selection for several important traits, including resistance to yellow rust, fusarium head blight and general Falat plant type. Genetic diversity of F5 and F6 lines was studied using 38 and 47 polymorphic loci produced by long AP-PCR primers. Results showed that there was a great diversity within and between studied advanced lines. Average gene diversity across polymorphic loci for two generations was 28% and 53%, ranging 9.1- 49.5% and 9.1-49.9%, respectively. In F5 we identified lines with low identity to Falat as few as 28% and some lines with high identity up to 79%. Average identity to Falat in F5 was 59.5%. In F6, however, we identified lines with 38-85% identity to Falat, and averaged to 65%. These results indicate that advancing lines from F5 to F6 increased their identity to Falat cultivar due to selection pressure in favor of Falat plant type. Our findings obviously show the multidirectional effects of selection made by breeders on genetic diversity of plant material at molecular level.